It is well known that extensive osteoclast formation plays a key role in osteoporosis in post-menopausal women and the elderly. The suppression of extensive osteoclastogenesis and bone resorption may be an effective preventive strategy for osteoporosis. Zoledronic acid (ZOL) has been indicated to play an essential role in regulating bone mineral density and has already been used in large clinical trials. However, the effects of ZOL on osteoclastogenesis remain to be fully elucidated. Therefore, the present study aimed to determine the effects of ZOL on osteoclastogenesis, and to explore the corresponding signalling pathways. By using a cell viability assay, as well as in vitro osteoclastogenesis, immunofluorescence and resorption pit assays, we demonstrated that ZOL (0.1-5 µ M) suppressed receptor activator of nuclear factor-κB ligand (RANKL)-induced osteoclast differentiation and bone resorptive activity. Furthermore, western blot analysis and reverse transcription-quantitative PCR indicated that ZOL inhibited the RANKL-induced activation of NF-κB and the phosphorylation of JNK in RAW264.7 cells, and subsequently decreased the expression of osteoclastogenesis-associated genes, including calcitonin receptor, tartrate-resistant acid phosphatase and dendritic cell-specific transmembrane protein. ZOL inhibited osteoclast formation and resorption in vitro by specifically suppressing NF-κB and JNK signalling. On the whole, the findings of this study indicate that ZOL may serve as a potential agent for the treatment of osteoclast-associated diseases, including osteoporosis.

Recognizing facial expressions is crucial for adaptive social interaction. Prior empirical research on facial expression processing has primarily focused on isolated faces; however, facial expressions appear embedded in surrounding scenes in everyday life. In this study, we attempted to demonstrate how the online car-hailing scene affects the processing of facial expression. This study examined the processing of drivers' facial expressions in scenes by recording event-related potentials, in which neutral or happy faces embedded in online car-hailing orders were constructed (with type of vehicle, driver rating, driver surname, and level of reputation controlled). A total of 35 female volunteers participated in this experiment and were asked to judge which facial expressions that emerged in scenes of online car-hailing were more trustworthy. The results revealed an interaction between facial expression scenes, brain areas, and electrode sites in the late positive potential, which indicated that happy faces elicited larger amplitudes than did neutral ones in the parietal areas and that scenes with happy facial expressions had shorter latencies than did those with neutral ones. As expected, the late positive potential evoked by happy facial expressions in a scene was larger than that evoked by neutral ones, which reflected motivated attention and motivational response processes. This study highlights the importance of scenes as context in the study of facial expression processing.